Which of the following is dioecious ?

Options

A. Maize
B. Cycas
C. Pinus
D. Both (a) and (b)

Answer

To determine which of the following options is dioecious, we need to understand the definitions of dioecious and monoecious plants.

### Step-by-Step Solution:

1. **Understand Dioecious and Monoecious**:
- **Dioecious**: This term refers to plant species where individual plants are either male or female. This means that the male and female reproductive organs are located on separate individuals.
- **Monoecious**: In contrast, monoecious plants have both male and female reproductive organs on the same individual plant.

2. **Analyze the Given Options**:
- **Maze (Maize)**: This is a monoecious plant. It has both male (tassels) and female (ears) reproductive structures on the same plant.
- **Cycas (Cyclus)**: This is a dioecious plant. Male and female reproductive structures are found on separate plants.
- **Pinus**: This is also a monoecious plant. It has both male (cones) and female (cones) reproductive structures on the same plant.

3. **Identify the Dioecious Plant**:
- From the analysis, Cycas is the only plant listed that is dioecious, as it has separate male and female plants.

### Conclusion:
The correct answer is **Cycas**, as it is the dioecious plant among the options provided.

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